Figure 4.

Metabolic network states under effect of glutamate uptake under normal physiological conditions. Histograms of the steady-state flux space are shown for glutamine, lactate, glucose, AKG (alfa-ketoglutarate), and ATP (adenosine triphosphate). During model simulation was observed that the glucose uptake, lactate, glutamine and AKG production increased with increase in glutamate (the glutamate uptake from 0, 03 to 0, 310). (A) Flux of alpha ketoglutarate increase dramatically, this is due to the activation of the deamination of the glutamate mediated by glutamate dehydrogenase. (B) activation of tricarboxilic cycle is induced by the previous obtention of AKG, as consequence ATP synthesis increases. (C) consumption of glucose is increased to satisfy the glycolitic state in astrocyte, however other sources of energy supply (D) related with the glutamine/glutamate cycle, glutamine are released to the extracellular space in order to satisfy neuronal needs. (E) lactate released during glutamate uptake.